EP0139105B1 - Apparat zum Verbrennen eines brennbaren Gases - Google Patents

Apparat zum Verbrennen eines brennbaren Gases Download PDF

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Publication number
EP0139105B1
EP0139105B1 EP84108437A EP84108437A EP0139105B1 EP 0139105 B1 EP0139105 B1 EP 0139105B1 EP 84108437 A EP84108437 A EP 84108437A EP 84108437 A EP84108437 A EP 84108437A EP 0139105 B1 EP0139105 B1 EP 0139105B1
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EP
European Patent Office
Prior art keywords
gas
gas burner
combustion
combustion chamber
chamber
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
EP84108437A
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English (en)
French (fr)
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EP0139105A1 (de
Inventor
Subhash C. Jatana
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Columbia Gas System Service Corp
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Columbia Gas System Service Corp
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Filing date
Publication date
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Priority to DE8686106296T priority Critical patent/DE3479754D1/de
Publication of EP0139105A1 publication Critical patent/EP0139105A1/de
Application granted granted Critical
Publication of EP0139105B1 publication Critical patent/EP0139105B1/de
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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23C—METHODS OR APPARATUS FOR COMBUSTION USING FLUID FUEL OR SOLID FUEL SUSPENDED IN  A CARRIER GAS OR AIR 
    • F23C3/00—Combustion apparatus characterised by the shape of the combustion chamber
    • F23C3/004—Combustion apparatus characterised by the shape of the combustion chamber the chamber being arranged for submerged combustion
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23D—BURNERS
    • F23D14/00—Burners for combustion of a gas, e.g. of a gas stored under pressure as a liquid
    • F23D14/34—Burners specially adapted for use with means for pressurising the gaseous fuel or the combustion air
    • F23D14/36—Burners specially adapted for use with means for pressurising the gaseous fuel or the combustion air in which the compressor and burner form a single unit
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24H—FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
    • F24H1/00—Water heaters, e.g. boilers, continuous-flow heaters or water-storage heaters
    • F24H1/18—Water-storage heaters
    • F24H1/20—Water-storage heaters with immersed heating elements, e.g. electric elements or furnace tubes
    • F24H1/205—Water-storage heaters with immersed heating elements, e.g. electric elements or furnace tubes with furnace tubes
    • F24H1/206—Water-storage heaters with immersed heating elements, e.g. electric elements or furnace tubes with furnace tubes with submerged combustion chamber
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24H—FLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
    • F24H8/00—Fluid heaters characterised by means for extracting latent heat from flue gases by means of condensation
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B30/00—Energy efficient heating, ventilation or air conditioning [HVAC]

Definitions

  • This invention relates to an apparatus for burning a combustible gas.
  • the latest furnaces are considerably more efficient than the older, pilot ignition gas furnaces; a typical pilot ignition gas furnace might have a steady state efficiency of about 75% and a seasonal efficiency of about 65%, while replacing the pilot light with either direct spark ignition or intermittent pilot ignition increases the seasonal efficiency to about 70%. Certain of the high-efficiency gas furnaces previously mentioned have seasonal efficiencies of about 80-90%.
  • Most residential gas water heaters comprise a cylindrical water tank provided with an insulating jacket and a gas burner which impinges upon the base of the water tank; to allow escape of combustion products produced by the burning gas, a vertical conduit carrying the exhaust products extends vertically upwardly along the axis of the cylindrical tank, this vertical conduit serving to effect additional heat exchange between the combustion products and the water in the tank.
  • This British Patent Application describes apparatus for burning a combustible gas, the apparatus comprising a housing having within its interior a liquid chamber capable of holding liquid, a hollow, liquid-impervious combustion chamber member disposed within the liquid chamber and having within its interior a combustion chamber, an exhaust conduit having an inlet connected to the combustion chamber and an outlet through which combustion products can leave the apparatus, the exhaust conduit comprising a heat exchanger for effecting heat exchange between the combustion products produced by combustion within the combustion chamber, this heat exchanger comprising a helical section extending downwardly through the liquid chamber, a gas burner disposed within the combustion chamber, and an impeller for passing combustible gas to the gas burner.
  • This apparatus uses a burner of conventional type, which is fed solely with combustible gas and which is surrounded by a combustion chamber which supplies the air necessary for combustion. Furthermore, in this apparatus, the helical section is connected directly to the combustion chamber.
  • This invention provides an apparatus of the same general type as that described in the aforementioned British Patent Application, but which uses a novel form of heat exchanger to increase the efficiency of the space heating system.
  • this invention provides apparatus for burning a combustible gas, the apparatus comprising a housing having within its interior a liquid chamber capable of holding liquid; a hollow, liquid-impervious combustion chamber member disposed within the liquid chamber and having within its interior a combustion chamber; an exhaust conduit having an inlet connected to the combustion chamber and an outlet through which combustion products can leave the apparatus, the exhaust conduit comprising a heat exchanger for effecting heat exchange between the combustion products produced by combustion within the combustion chamber, this heat exchanger comprising a helical section extending downwardly through the liquid chamber; a gas burner disposed within the combustion chamber; and an impeller for passing combustible gas to the gas burner.
  • the apparatus of the invention is characterized in that the gas burner is hollow, having walls surrounding an internal chamber and apertures passing through these walls, thereby establishing fluid communication between the internal chamber of the gas burner and the combustion chamber outside the gas burner, the impeller is arranged to pass a combustible mixture of the combustible gas and air under pressure into the internal chamber of the gas burner, the impeller having a mixture control device for controlling the ratio of gas and air in this mixture, the apertures in the gas burner being sized such that combustion of the combustible mixture within the combustion chamber outside the gas burner will not cause ignition of the combustible mixture within the internal chamber of the gas burner, and the heat exchanger comprises a riser section extending upwardly from the combustion chamber, with the helical section extending downwardly frmm the upper end of the riser section.
  • the apparatus of this invention for burning combustible gas differs from conventional gas furnaces in which the combustible gas and air are mixed.
  • pure gas flows out of one or more gas nozzles, thereby becoming mixed with air to form a combustible mixture which burns immediately adjacent the gas nozzle.
  • the combustible gas and the air is pre-mixed to form a combustible mixture which is then forced into the internal chamber of the gas burner (in saying that, in the instant method, the combustible mixture is passed "under pressure" into the internal chamber of the gas burner, we mean only that the combustible mixture enters this internal chamber at a pressure greater than the pressure existing immediately outside the gas burner, so that the combustible mixture will flow out of the gas burner via the apertures therein).
  • the apertures in the gas burner are sized so that combustion of the gas around the gas burner will not cause ignition of the combustible mixture within the gas burner thus, preventing the occurrence of any flashback and/or explosion within the burner or impeller.
  • the pre-mixing of gas and air achieved in the apparatus and method of this invention enables the gas/air ratio to be precisely controlled, in contrast to a conventional furnace in which, because only combustible gas flows from the nozzle, only limited control can be exercised over the gas/air ratio.
  • Control of the gas/air ratio is important in achieving maximum efficiency of gas usage, since any excess of air over that required for combustion of the gas simply dilutes the combustion products, reducing the temperature thereof and thus redueing the efficiency of heat exchange between the combustion products and any heat exchanger which serves to remove heat from the combustion products and supply it to where it is needed.
  • combustion chamber in our apparatus may allow for the entry of some additional air thereinto, in addition to the combustible mixture issuing from the gas burner, we very much prefer that the combustion chamber have no gas inlet other than the gas burner and no outlet other than the exhaust conduit so that all the air required for combustion is mixed with the combustible gas prior to its entry into the gas burner.
  • the impeller forces a mixture of combustible gas and air into the gas burner.
  • the admixing of the combustible gas and air may be effected either upstream or downstream of the impeller; i.e. the combustible gas may be admixed with air upstream of the impeller and the resultant mixture passed through the impeller, or alternatively only air may pass through the impeller and admixing of the air with the combustible gas be effected between the impeller and the gas burner.
  • the impeller be of a type which will not generate sparks or the like capable of igniting the combustible mixture of gas and air passing through it; in the latter case, no such restriction on the type of impeller exists.
  • the amount of air mixed with the combusible gas before entry into the gas burner should be equal to the theoretical amount required for complete combustion of the combustible gas.
  • the amount of air mixed with the combustible gas to form the combustible mixture is desirably from 1 to about 1.2, and preferably about 1.1, times the amount of air or other oxygen-containing gas stoichiometrically required for complete combustion of the combustible gas.
  • the geometric shape of the gas burner is important in the apparatus and method of this invention.
  • the combustion and the gas burner of the apparatus have substantially the form of a pair of co-axial cylinders and the apertures in the gas burner are disposed in the cylindrical wall of the gas burner, thereby permitting combustion of the combustible mixture on a cylindrical flame front surrounding the gas burner.
  • This cylindrical flame front allows for very good heat transmission from the flame to the cylindrical wall of the combustion chamber which, when the apparatus is in use, is immersed in liquid held in the liquid chamber, and thus promotes very efficient heat transfer from the flame to the liquid.
  • this end wall may or may not be provided with apertures, i.e.
  • the cylindrical burner may have apertures in the side walls only or in both the side walls and the end wall.
  • Other shapes of gas burner may also be employed; for example, the burner may be conical, frusto-conical or hemispherical or have the form of a hemisphere truncated by a plane parallel to its base.
  • a cylindrical gas burner having apertures only in the side walls is the most efficient form.
  • the part of the combustion chamber surrounding the gas burner has substantially the same form as the burner.
  • the combustion chamber has the form of a cylinder surmounted by an upwardly-tapering frustum of a cone
  • the inlet of the exhaust conduit is connected to the narrow end of the frusto-conical portion of the combustion chamber
  • the gas burner has the form of a cylinder substantially co-axial with the cylindrical portion of the combustion chamber and the apertures of the gas burner are disposed in the cylindrical wall of the gas burner, thereby permitting combustion of the combustible mixture on a cylindrical flame front surrounding the gas burner.
  • the apparatus of the invention also uses a special type of exhaust conduit to promote very efficient heat transfer from the combustion products to liquid in the liquid chamber.
  • the part of the exhaust conduit which acts as a heat exchanger has a riser section extending upwardly from the combustion chamber and a helical section extending downwardly from the upper end of the riser.section. It has been found that this form of exhaust conduit provides very efficient heat transfer from the combustion products to liquid in the liquid chamber because the downward slope of the helical section contributes to a higher coefficient of convective heat transfer (since the coolest downstream section of the heat exchanger is in contact with the coolest water lying in the lower part of the liquid chamber) and therefore to higher efficiency of heat exchange.
  • the lower end of the helical section of the exhaust conduit is disposed adjacent the lowest part of the liquid chamber; since water heated by the exhaust conduit tends to rise within the liquid chamber, it is desirable that the lower end of the heat exchanger extend adjacent the lowest part of the liquid chamber in order to ensure that a large mass of cold liquid is not left below the heat exchanger and remains unheated thereby.
  • the exhaust conduit is desirably provided with a condensate trap for draining condensate produced by cooling of the combustion products in the heat exchanger, this condensate trap comprising a first conduit extending downwardly from the lower end of the helical section of the exhaust conduit, a second conduit extending upwardly from the lower end of the first conduit, and a drain conduit extending downwardly from adjacent the junction of the first and second conduits, this drain conduit including a U-bend to trap condensed water and prevent the exit of combustion products through the drain conduit.
  • the apparatus of the invention will, of course, normally incorporate a liquid supply line through which liquid can be supplied to the liquid chamber. Desirably, a portion of the liquid supply line is in contact with the exhaust conduit so that heat transfer can occur from the combustion products passing along the exhaust conduit to liquid in the liquid supply line.
  • FIG. 10 shows a vertical section through the apparatus.
  • This drawing shows an apparatus of the invention (generally designated 10) which comprises a substantially cylindrical housing or water tank 12 generally similar to the tank of a conventional water heater except that it lacks the normal central, vertical exhaust conduit.
  • the tank 12 is surrounded by an outer cylinder 14 and an annular insulating jacket 16 is disposed between the tank 12 and the outer cylinder 14 to reduce heat loss from the tank 12.
  • the upper end of the outer cylinder 14 is closed by an end plate 18; the insulating jacket 16 also fills the space between the end plate 18 and the adjacent upper end wall of the tank 12 in order to reduce heat loss from the end wall of the tank 12.
  • the lower end of the outer cylinder 14 extends downwardly beyond the lower end of the tank 12 and is closed by a base plate 20 which rests upon a floor or other suitable support surface and thus supports the entire apparatus.
  • a pad 22 of the same insulating material as the jacket 16 is disposed above the base plate 20 to reduce heat loss via the baseplate.
  • the lower end wall 24 of the tank 12 has fixed thereto a drain tube 26 provided with a manually-operable valve 28 which is normally closed but which can be opened when it is-desired to drain liquid from the tank 12.
  • a manually-operable valve 28 which is normally closed but which can be opened when it is-desired to drain liquid from the tank 12.
  • the tank 12 is completedly filled with water.
  • the central portion of the lower-end wall 24 is flat and has a central circular aperture cut therein. This circular aperture surrounded by a planar flange 30 which forms part of the lower end-wall of a combustion chamber member 32.
  • This combustion chamber member 32 lies wholly within the tank 12, is cylindro-conical in form having the circular plate 30 as part of its base, a cylindrical side wall section 34 extending upwardly from around the periphery of the plate 30 and an upper, upwardly tapering frusto-conical section 36 surmounting the upper end of the cylindrical section 34.
  • the various sections of the combustion chamber member 32 enclose a cylindro-conical combustion chamber 38.
  • a gas burner 40 having the form of a hollow cylinder closed at its upper end but open at its lower end.
  • the gas burner 40 extends downwardly through the central circular aperture in the lower-end wall 24 and has a flange 42 extending radially outwardly below the flange 30.
  • the cylindrical wall of the gas burner 40 has a multitude of small apertures passing therethrough, thereby establishing fluid communication between the internal chamber within the hollow cylindrical gas burner 40 and the combustion chamber 38 lying outside the gas burner 40.
  • a combustible mixture of natural gas and air is fed under pressure to the internal chamber of the gas burner 40 from an impeller 46 located between the lower end wall 24 of the tank 12 and baseplate 20.
  • the impeller 46 is provided, at its outlet end, with a flange 47 for attachment to flange 42 on the gas burner 40.
  • the flange 30 is provided with four equally-spaced threaded studs 44 which extend downwardly through bores (not shown) provided in the flanges 42 and 47 on the gas burner 40 and the impeller 46.
  • Nuts 45 are screwed on to the lower ends of the studs 44, thereby securing the flanges 30, 42 and 47 together and establishing a gas-tight connection between the impeller 46 and the interior of the gas burner 40.
  • Gaskets (not shown) may of course be provided between adjacent pairs of the flanges 30, 42 and 47 to assist in obtaining good seals.
  • the impeller 46 may be of any convenient type and could be, for example, a vane pump or a fan. Since, as described in more detail below the impeller 46 is required to pump a combustible mixture of natural gas and air, the impeller must in practice be of a type which can pump such combustible gas without any risk of explosion, but it is believed that those skilled in this field will have no difficulty in providing an impeller which meets these requirements. (Alternatively, if mixing of the natural gas and air is arranged to take place downstream of the impeller, the impeller need not be of any specific type). The impeller 46 is driven by an electric motor (not shown).
  • the impeller 46 draws its air from an air-inlet tube 48.
  • the inlet end (not shown) of this tube 48 is preferably located externally of the building in which the apparatus is installed in order that the air drawn into the impeller will be unconditioned, external air and not air which is already conditioned.
  • the portion of the tube 48 adjacent the main part of the apparatus 10 comprising a horizontal limb which terminates above the upper endplate 18, a vertical limb which extends vertically downwardly between the cylindrical walls of the tank 12 and the outer cylinder 14 within the insulating jacket 16, and a second horizontal limb which extends to the intake of the impeller 46.
  • the shape of the tube 48 is of course dictated solely by the type and position of air intake port with which the apparatus 10 is intended to be used and may vary almost indefinitely.
  • tube 48 could terminate flush with the upper surface of the endplate 18 but such an arrangement would have the obvious disadvantage of drawing combustion air from within the building rather than using unheated outside air.
  • the tube 48 could be replaced by a simple horizontal tube extending outwardly from the impeller 46 i.e. by a horizontal tube which is in effect an extension of the second horizontal limb shown).
  • This placement of the tube 48 is designed so that none of the tube 48, which is made of polyvinyl chloride, protrudes from the cylindrical wall of the outer cylinder 14, since any protruding parts of the tube would be susceptible to damage during transit (if in place during such transit), or damage after installation caused by, for example, children, household pets, or careless handymen.
  • a mixture control device in the form of a manually-operable butterfly valve 50 is disposed in the second horizontal limb of the tube 48 (but may alternatively be disposed in the vertical limb of the tube 48); this valve permits adjustment of the natural.gas/air ratio in the mixture provided by the impeller 46 to the gas burner 40 and is accessible via a removable panel (not shown) in the outer cylinder 14; naturally, a corresponding aperture is provided in the insulating jacket 16 adjacent this removable panel.
  • the placement of the valve 50 is designed to permit ready adjustment of the valve 50 by the person installing the apparatus but to render later access by other persons difficult in order to ensure, as far as possible, that untrained persons do not attempt to adjust this valve setting, since improper adjustment could result in incomplete combustion of the natural gas or other undesirable consequences.
  • Natural gas is supplied to the impeller via a gas line 52 provided with a gas valve 53; the line 52 intersects the second horizontal limb of the tube 48 immediately adjacent the inlet of the impeller 46.
  • the combustion chamber 38 contains an electrical ignition device 54 which can be of any conventional type and which is used in the conventional manner to ignite the combustible gas/air mixture emerging from the gas burner 40, and a flame sensor 56 which is also of a conventional type and which serves to check that the gas/air mixture emerging from the gas burner 40 has been correctly ignited by the ignition device 54.
  • the purpose of the flame sensor 56 will be described in more detail below. (The electrical ignition device 54 and the flame sensor 56 may alternatively be combined into a single device which performs both functions).
  • the combustion products produced by burning of the gas/air mixture within the combustion chamber 38 pass through an exhaust conduit including a heat exchanger comprising a riser section 58 which is connected to the upper, narrower end of, and extends vertically upwardly from, the frusto-conical section 36 of the combustion chamber member, and a helical section 60, which extends downwardly from the upper end of the riser section 58.
  • the riser section 58 lies along the axis of the tank 12 and the axis of the helical section 60 coincides with the axis of the tank 12.
  • this form of heat exchanger provides a very efficient heat transfer from the combustion products to water in the tank 12, because the downward slope of the helical section 60 contributes to a higher coefficient of convective heat transfer (since the coolest downstream section of the heat exchanger is in contact with the coolest water adjacent the base of the tank 12) and therefore to higher efficiency of the heat exchanger.
  • the lower end of the helical section 60 lies adjacent the base 24 of the tank 12; since water heated by the heat exchanger tends to rise within the tank 12, it is desirable that the lower end of the heat exchanger extend adjacent the base of the tank 12 in order to ensure that a large mass of cold water is not left below the heat exchanger and remains unheated thereby.
  • the combustion products leaving the lower end of the helical section of the heat exchanger pass through a further portion of the aforementioned exhaust conduit which acts as a condensate trap, this further portion, including a first vertical section 62 extending vertically downwardly from the lower end of the helical section 60 through the base 24 of the tank 12, a short horizontal section 64 which extends into the insulating blanket 16, and a second, long vertical section 66 which extends vertically upwardly from the horizontal section 64 through the insulating blanket 16 and through an aperture provided in the upper end plate 18. From the upper end of the second vertical section 66, a horizontal section 68 carries the combustion products out of the building in which the apparatus is installed.
  • the form of the section 68 may vary for the reasons already stated in relation to the corresponding section of the inlet tube 48, and similarly the vertical section 66 and/or horizontal section 68 may be omitted entirely).
  • the placement of the second vertical section 66 within the insulating blanket 16 serves to prevent accidental damage to the second vertical section, as already described in relation to the air inlet tube 48.
  • a water supply line 70 used to supply water to the tank 12 passes through an aperture provided in the upper endplate 18 and then passes vertically downwardly within the second vertical section 66 of the exhaust conduit, along the first horizontal section 64 of this conduit and then vertically upwardly through an aperture provided in the base 24 of the tank 12 into the interior of that tank.
  • the disposition of the water supply line 70 within the sections 66 and 64 of the exhaust conduit allows countercurrent flow between water passing along the line 70 and combustion products passing along the section 66 and 64, and allows heat exchange to take place between the combustion products passing along the exhaust conduit and the water entering the tank via the water supply line, thus pre-warming the water entering the tank 12 and further cooling the combustion products, thereby increasing the efficiency of the apparatus.
  • the water supply line is provided an U-bend 72; this U-bend reduces the tendency for water warmed by heat transfer from the combustion products passing along the exhaust conduit from rising into the portion of the water supply line 70 lying above the upper endplate 18.
  • Such back-flow of water into the part of the water supply line 70 lying above the plate 18 is obviously undesirable since it leads to heat loss from the apparatus, thus reducing the efficiency thereof.
  • the resultant leakage of hot water into the cold water system may produce undesirable changes in temperature therein.
  • the U-shape formed by the sections 62, 64 and 66 serves as a condensate trap.
  • a drain conduit 74 extends downwardly from the first horizontal section 64 and serves to drain condensate therefrom.
  • the drain conduit 74 is provided with a U-bend below the first horizontal section 64; this U-bend rapidly becomes filled with condensate when the apparatus is in operation, and the condensate filling the lowest part of the U-bend acts as a liquid seal to prevent gaseous combustion products flowing out through the drain conduit 74.
  • the outlet end (not shown) of the drain conduit 74 is connected to a suitable drain line.
  • the apparatus 10 serves as both a water heater and a space heater or furnace.
  • a water outlet line 76 extends from within the tank 12 through the upper end wall of the tank and through the upper endplate 18. This water outlet tube 76 serves to supply hot water for domestic use, as indicated schematically by a branch line.
  • Another branch line 80 leaves the water output line 76 a short distance above the upper endplate 18 and acts as a water supply line to supply hot water from the tank 12 to a water inlet of a space heating assembly comprising a second heat exchanger in the form of a coil 82 disposed within a duct 84, which forms part of the ductwork of a conventional forced-air domestic space heating system.
  • Air is forced over the coil 82 by means of a thermostatically-controlled fan 86 (shown only schematically).
  • Water from a water outlet of the coil 82 is returned to the tank via a water return line 88, which intersects the water supply line 70 a short distance above the upper endplate 18.
  • water returning from the coil 82 to the tank flows through the section of the liquid supply line 70 lying within the sections 66 and 64 of the exhaust conduit, thereby causing the returning water to flow countercurrent to, and receive heat from, the combustion products passing along these sections of the exhaust conduit.
  • the apparatus 10 can also be used. in conjunction with a baseboard radiator or other type of hot water space heating system.
  • a typical 100,000 Btu/hr. (25,200 KCal/ hr.) apparatus for domestic use may have a tank 12 having a capacity of about 40 U.S. gallons (151 liters) and approximately 16 inches (45 cm.) in diameter.
  • a unit would use 100 cubic ft. (2.83 m 3 ) of natural gas per hour and approximately 11,000 cubic ft. (311 m 3 ) of air per hour, assuming that the amount of air is set at the optimum value of approximately 10% above that stoichiometrically required for combustion of the gas.
  • This gas/air mixture will be forced by the impeller 46 at a pressure of approximately 4 inches (10 cm.) water gauge pressure into the internal chamber of the gas burner 40; it should be noted that this operating pressure is considerably greater than that employed in supplying air to most gas furnaces since the resistance to flow provided by the apertures in the gas burner and by the heat exchanger 58, 60 requires a considerably greater operating pressure.
  • the cylindrical portion of the gas burner 40 has a length of approximately 4 inches (10 cm.) and a diameter of approximately 2.2 inches (5.5 cm.).
  • the uppermost 3 inches (7.5 cm.) of the cylindrical wall of the gas burner 14 is pierced by apertures having a diameter of 0.033-0.036 inches (0.84-0.91 mm.) (though the apertures could vary within the range of 0.020-0.062 inches (0.50-1.57 mm.) if desired) spaced on a square grid at intervals of approximately 0.070 inches (1.78 mm.); the lines within this grid run parallel to the axis of the cylindrical gas burner 40 and on circles running around the gas burner.
  • the helical section 60 of the heat exchanger is formed of a stainless steel tube of diameter not greater than 2 inches (5 cm.) and has a total length of approximately 30 ft. (9.1 m.).
  • the apparatus does not need a chimney or a class A or B vent; the outlet from the exhaust conduit may be discharged through corrosion resistant tubing through any convenient external surface of the building in which the apparatus is installed. It should be noted that the combined steady-state efficiency of water and space heating of about 95% is greater than that of any combined system available.
  • the heating coil 82, the duct 84 and the fan 86 could be replaced by one or more conventional water-filled radiators for space heating purposes, a forced-air system being shown in the drawing simply because this is the most common type of system used in domestic space heating.
  • water-filled radiators are to be used in space heating, it will be necessary to provide the water outlet line 76 or the return line 88 with a circulating pump to effect circulation of water through the radiators. (In practice, although not shown in the accompanying drawing, a circulating pump will in practice usually be necessary in forced-air systems also).
  • the flame sensor 56 is provided within the combustion chamber 38 to detect an absence of flame due either to failure of the ignition device 54 or to failure to supply proper quantities of gas because of improper operation of the impeller 46.
  • the flame sensor 56 is arranged to close a switch (not shown) which shuts down the impeller 46.
  • the air inlet line 48 is provided with a pressure sensor (not shown) adjacent the inlet to the impeller 46.
  • the pressure sensor is arranged to shut the impeller down.
  • the pressure sensor is also arranged to shut the impeller down if excessive suction exists in the line 48 as a result of, for example, obstruction of the air intake to this line by debris or other materials.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Instantaneous Water Boilers, Portable Hot-Water Supply Apparatuses, And Control Of Portable Hot-Water Supply Apparatuses (AREA)
  • Incineration Of Waste (AREA)

Claims (7)

1. Vorrichtung (10) zum Verbrennen eines brennbaren Gases, welche umfaßt:
-ein Gehäuse (12) mit einer in seinem Inneren befindlichen Flüssigkeitskammer, welche Flüssigkeit enthalten kann;
-ein hohles, flüssigkeitsdurchlässiges Verbrennungskammerteil (32), welches innerhalb der Flüssigkeitskammer angeordnet ist und in seinem Inneren eine Verbrennungskammer (38) aufweist;
-ein Abgasrohr (58, 60, 62, 64, 68) mit einem der Verbrennungskammer (38) verbundenen Einlaß und einem Auslaß, durch welchen Verbrennungsprodukte die Vorrichtung verlassen können, wobei das Abgasrohr (58, 60, 62, 64, 68) einen Wärmeaustauscher (58; 60) zum Wärmeaustausch zwischen den durch die Verbrennung innerhalb der Verbrennungskammer (38) entstandenen Verbrennungsprodukten umfaßt und wobei dieser Wärmeaustauscher (58, 60) einen spiralförmigen Abschnitt (60) umfaßt, der sich durch die Flüssigkeitskammer nach unten erstreckt;
-einen innerhalb der Verbrennungskammer (38) angeordneten Gasbrenner (40); und
-ein Gebläserad (46) zum Weiterleiten von brennbarem Gas zu dem Gasbrenner (40),

dadurch gekennzeichnet, daß der Gasbrenner (40) hohl ist und eine Innenkammer umgebende Wände und durch diese Wände hindurchgehende Öffnungen hat, wodurch eine Flüssigkeitsverbindung zwischen der Innenkammer des Gasbrenners (40) und der Verbrennungskammer (38) außerhalb des Gasbrenners (40) entsteht, daß das Gebläserad (46) so angeordnet ist, daß es ein brennbares Gemisch des brennbaren Gases und Druckluft in die Innenkammer des Gasbrenners (40) weiterleitet, wobei das Gebläserad (46) eine Gemischreguliereinrichtung (50) zum Regulieren des Gas-Luft-Verhältnisses in diesem Gemisch aufweist und die in dem Gasbrenner (40) befindlichen Öffnungen so dimensioniert sind, daß die Verbrennung des brennbaren Gemisches in der Verbrennungskammer (38) außerhalb des Gasbrenners (40) nicht zum Entzünden des brennbaren Gemisches innerhalb des Innenkammer des Gasbrenners (40) führt und daß der Wärmeaustauscher (58, 60) einen sich von der Verbrennungskammer nach oben erstreckenden Steigabschnitt (58) umfaßt, wobei sich der spiralförmige Abschnitt (60) von dem oberen Ende des Steigabschnitts (58) nach unten erstreckt.
2. Vorrichtung nach Anspruch 1, worin die Verbrennungskammer (38) als Einlaß nur den Gasbrenner (40) und als Auslaß nur des Abgasrohr (58, 60, 62, 64, 66, 68) aufweist.
3. Vorrichtung nach Anspruch 1 oder 2, dadurch gekennzeichnet, daß die Gemischreguliereinrichtung (50) so angeordnet ist, daß sie ein brennbares Gemisch erzeugt, dessen Luftmenge das 1- bis 1,2 fache der Luftmenge beträgt, die zur vollständigen Verbrennung des in dem brennbaren Gemisch befindlichen Gases benötigt wird.
4. Vorrichtung nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, daß die Verbrennungskammer die Form eines Zylinders (34) hat, der von einem nach oben zu schmaler werdenden Kegelstumpf (36) umgeben ist, daß der Einlaß des Abgasrohrs (58, 60, 62, 64, 66, 68) mit dem schmalen Ende des kegelstumpfförmigen Teils (36) der Verbrennungskammer (38) verbunden ist, der Gasbrenner (40) die Form eines Zylinders hat, welcher im wesentlichen koaxial mit dem zylindrischen Teil (34) der Verbrennungskammer (38) ist, und daß die Öffnungen des Gasbrenners (40) in der zylindrischen Wand des Gasbrenners angeordnet sind und so die Verbrennung des brennbaren Gemisches auf einer zylindrischen, den Gasbrenner (40) umgebenden Flammenfront ermöglichen.
5. Vorrichtung nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, daß die Öffnungen in dem Gasbrenner (40) einen Durchmesser von 0,5 bis 1,57 mm haben und auf einem viereckigen Gitter in einem' Abstand von ca. 1,78 mm zueinander liegen.
6. Vorrichtung nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, daß das Abgasrohr außerdem einen Kondensatabscheider (62, 64, 66, 74) zum Ableiten des Kondensats enthält, das durch Kühlen der Verbrennungsprodukte in dem Wärmeaustauscher (58, 60) erzeugt wurde, wobei dieser Kondensatabscheider (62, 64,66,74) ein erstes, sich von dem hunteren Ende des spiralförmigen Abschnitts nach unten erstrekkendes Rohr (62), ein zweites, sich von dem unteren Ende des ersten Rohrs (64) nach oben erstreckendes Rohr (66) und ein sich neben dem Übergang zwischen ersten und zweitem Rohr (64, 66) nach unten erstreckendes Ableitrohr (74) umfaßt, wobei das Ableitrohr (74) U-förmig ist, um kondensiertes Wasser abzuscheiden und den Austritt von Verbrennungsprodukten durch das Ableitrohr (74) zu verhindern.
7. Vorrichtung nach einem der vorhergehenden Ansprüche, die eine Flüssigkeitszuflußleitung (70) hat, durch die Flüssigkeitskammer mit Flüssigkeit versorgt werden kann, und dadurch gekennzeichnet ist, daß ein Teil der Flüssigkeitszuflußleitung (70) mit einem Teil des außerhalb der Flüssigkeitskammer befindlichen Abgasrohrs in Berührung ist, so daß ein Wärmeaustausch zwischen den durch das Abgasrohr (58, 60, 62, 64, 66, 68) hindurchströmenden Verbrennungsprodukten und der Flüssigkeit in der Flüssigkeitszuflußleitung (70) stattfinden kann.
EP84108437A 1983-07-20 1984-07-17 Apparat zum Verbrennen eines brennbaren Gases Expired EP0139105B1 (de)

Priority Applications (1)

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US515642 1983-07-20
US06/515,642 US4541410A (en) 1983-07-20 1983-07-20 Apparatus and method for burning a combustible gas, and a heat exchanger for use in this apparatus

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CA (1) CA1245920A (de)
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DK (2) DK162952C (de)
IE (2) IE56071B1 (de)

Families Citing this family (48)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4664096A (en) * 1979-12-10 1987-05-12 Narang Rajendra K Oil and gas water heater
US5020512A (en) * 1984-08-09 1991-06-04 State Industries, Inc. Water heater construction and method of heating water
FR2576404B1 (fr) * 1985-01-21 1989-06-09 Gaz De France Echangeur de chaleur et application a un appareil de rechauffage d'un fluide, notamment accumulateur d'eau chaude sanitaire
DE3536667A1 (de) * 1985-10-15 1987-04-16 Richard Vetter Geraet zum erwaermen von wasser, insb. warmwasserheizkessel
NL8600248A (nl) * 1986-01-31 1987-08-17 Atag Bv Apparatenfab Verwarmingsinrichting omvattende een brander van het type waaraan een nagenoeg stoechiometrisch brandstof/luchtmengsel wordt toegevoerd.
US4766883A (en) * 1986-02-26 1988-08-30 Mor-Flo Industries, Inc. Forced draft controlled mixture heating system using a closed combustion chamber
US4751914A (en) * 1987-01-08 1988-06-21 Ecodyne Corporation Atmospheric gas burner
US4790290A (en) * 1987-09-28 1988-12-13 A. O. Smith Corporation Method and apparatus for foam insulating a vessel
US4938204A (en) * 1989-08-18 1990-07-03 Pvi Industries, Inc. Water heater or boiler with improved thermal efficiency
US4993402A (en) * 1989-12-18 1991-02-19 Carrier Corporation Fuel efficient rapid response water heating module
US5022352A (en) * 1990-05-31 1991-06-11 Mor-Flo Industries, Inc. Burner for forced draft controlled mixture heating system using a closed combustion chamber
US5085579A (en) * 1991-03-25 1992-02-04 Mor-Flo Industries, Inc. Powered chamber combustion system and burner therefor
US5115798A (en) * 1991-08-08 1992-05-26 Mor-Flo Industries, Inc. Condensate trap
US5105799A (en) * 1991-09-25 1992-04-21 Wigdahl Arthur G Portable fluid heater
US5240411A (en) * 1992-02-10 1993-08-31 Mor-Flo Industries, Inc. Atmospheric gas burner assembly
US5197415A (en) * 1992-04-02 1993-03-30 Rheem Manufacturing Company Wet-base, down-fired water heater
CA2130961C (en) * 1993-12-01 2004-01-20 Henry Jack Moore Jr. Induced draft combustion water heater
US5357907A (en) * 1993-12-14 1994-10-25 Sabh (U.S.) Water Heater Group, Inc. Water heater with reduced localized overheating
FR2714719B1 (fr) * 1994-01-05 1996-02-09 Ctd Technologie Dispositif pour le chauffage simultané, à l'aide d'une même source de chaleur, de l'eau d'un circuit fermé de chauffage et de l'eau d'un circuit d'eau chaude sanitaire.
US5544645A (en) * 1994-08-25 1996-08-13 Lennox Industries Inc. Combination water heating and space heating apparatus
DE4443715C2 (de) * 1994-12-09 1997-04-17 Solvis Solarsysteme Gmbh Warmwasserbereiter
CH690136A5 (de) * 1996-03-01 2000-05-15 Werner Ris Heizanlage mit Wärmetauscher.
US6109339A (en) * 1996-07-15 2000-08-29 First Company, Inc. Heating system
US5699756A (en) * 1996-10-08 1997-12-23 Rheem Manufacturing Co. Wet-base, down-fired water heater
KR20010025007A (ko) 1998-05-13 2001-03-26 그레고리 제이. 맨쿠소 가스 연소 부스터
US6109216A (en) 1999-07-22 2000-08-29 Aos Holding Company Flammable vapor resistant water heater
US7559293B2 (en) 2002-06-04 2009-07-14 Bradford White Corporation High efficiency water heater
US6681723B1 (en) 2003-02-12 2004-01-27 Marvin Amendt Hot water heater
US6857578B2 (en) 2003-05-15 2005-02-22 Lennox Manufacturing Inc. Combination water heating and space heating apparatus and control therefor
WO2006051266A1 (en) * 2004-11-12 2006-05-18 Zenex Technologies Limited Heat exchanger suitable for a boiler, and a boiler including such a heat exchanger
US7032543B1 (en) * 2005-01-12 2006-04-25 Aos Holding Company Water heater with pressurized combustion
US7634977B2 (en) * 2006-08-16 2009-12-22 Aos Holding Company Gas water heater
US8024871B2 (en) * 2006-11-08 2011-09-27 Lg Electronics Inc. Exhaust structure for clothes dryer in apartment building
ITPD20070388A1 (it) * 2007-11-19 2009-05-20 Sit La Precisa S P A Con Socio Bruciatore, in particolare bruciatore a gas con pre-miscelazione
US8161918B2 (en) * 2008-08-25 2012-04-24 Aos Holding Company Water heater
EP2282153A1 (de) 2009-06-26 2011-02-09 OS Teknik Doppeltank zur Zimmerbeheizung und Leitungswassererhitzung
US9004018B2 (en) * 2010-03-08 2015-04-14 Rheem Manufacturing Company High efficiency gas-fired water heater
US8457835B2 (en) * 2011-04-08 2013-06-04 General Electric Company System and method for use in evaluating an operation of a combustion machine
AU2012201178B2 (en) * 2012-02-28 2014-07-03 Rheem Manufacturing Company High Efficiency Gas-Fired Water Heater
US9714774B2 (en) 2012-08-22 2017-07-25 Rheem Manufacturing Company Downfired high efficiency gas-fired water heater
US20150308711A1 (en) 2014-04-28 2015-10-29 Idalex Technologies, Inc. Heat Recovery Method and Apparatus
US9702567B2 (en) * 2014-11-14 2017-07-11 William D. Owen Heater system
US10767902B2 (en) 2015-11-13 2020-09-08 Thermasi Llc Electric resistance radiant furnace with mesh, screen, or honeycomb between panel emitters
JP6542659B2 (ja) * 2015-12-25 2019-07-10 リンナイ株式会社 燃焼装置
CN105627559A (zh) * 2016-03-09 2016-06-01 钟康亮 宝塔螺旋式多功能热水器、炉
CN105865016A (zh) * 2016-06-15 2016-08-17 任福杰 一种高压高温热水供给装置
US11519635B2 (en) * 2018-08-24 2022-12-06 Gas Technology Institute Gas fired process heater with ultra-low pollutant emissions
IT202100030593A1 (it) 2021-12-02 2023-06-02 La Nuova Coterm Srl Caldaia e suo uso

Family Cites Families (28)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US410620A (en) * 1889-09-10 Whitfield ward
US1107534A (en) * 1912-11-23 1914-08-18 Luther D Lovekin Water-heater.
US2048242A (en) * 1935-08-26 1936-07-21 Yates George Apparatus for the utilization of waste heat
US2080949A (en) * 1935-08-28 1937-05-18 William L Mccombs Heater
US2250892A (en) * 1939-07-29 1941-07-29 Mazer Alfred Teakettle
US2787318A (en) * 1949-11-04 1957-04-02 John J Wolfersperger Burner with tangential air admission and restricted throat
US3212493A (en) * 1961-08-18 1965-10-19 Phillips Petroleum Co Gas-fired heater with remote air inlet
US3500817A (en) * 1968-03-25 1970-03-17 Hydronics Systems Inc Liquid heating device
US3802397A (en) * 1969-02-05 1974-04-09 Nat Steel Construction Co Water heater and method of constructing the same
USRE27396E (en) * 1971-01-06 1972-06-20 Warm air furnace with radiant burner
US4271789A (en) * 1971-10-26 1981-06-09 Black Robert B Energy conversion system
US3934572A (en) * 1973-04-02 1976-01-27 Teague Jr Walter Dorwin Infrared space heater
ES437211A1 (es) * 1974-04-29 1977-02-01 Thurley Ltd John Aparato de intercambio termico.
NL158918B (nl) * 1975-08-12 1978-12-15 Rheem Bv Centrale verwarmingsketel.
US4227647A (en) * 1977-05-25 1980-10-14 Leif Eriksson Device for cooling chimney gases
US4175518A (en) * 1978-02-21 1979-11-27 Reames Cedric Ted A Jr Preheater device for hot water heaters
US4170199A (en) * 1978-05-22 1979-10-09 Regor Energy Saver Inc. Closed heat transfer system
US4178907A (en) * 1978-07-27 1979-12-18 Sweat James R Jr Unified hot water and forced air heating system
FR2442408A1 (fr) * 1978-11-27 1980-06-20 Rech Produits Et Chaudiere de chauffage central
IT7920865V0 (it) * 1979-02-22 1979-02-22 Vezzoli Louis Alex Generatore catalitico d'aria calda e d'acqua calda.
FR2479956A1 (fr) * 1980-04-02 1981-10-09 Collard Trolart Sa Appareil de rechauffage d'un liquide
US4301772A (en) * 1980-06-02 1981-11-24 A. O. Smith Corporation Water heating apparatus
US4371111A (en) * 1980-06-24 1983-02-01 Pernosky Richard J Home heating system employing water heater as heating source
KR810001688Y1 (ko) * 1980-07-28 1981-10-27 박기동 방사상 흡연구를 형성한 온수 보일러
CA1160916A (en) * 1981-04-01 1984-01-24 Lars-Olof Borking Boiler for domestic heating system
GB2103343B (en) * 1981-06-19 1984-12-19 John Edward Bowen Heating apparatus
FR2513745A1 (fr) * 1981-09-29 1983-04-01 Vidalenq Maurice Chauffe-eau a accumulation et a gaz
JPS5895143A (ja) * 1981-11-30 1983-06-06 Toshiba Corp パルス燃焼方式の給湯機

Also Published As

Publication number Publication date
DK162952C (da) 1992-05-25
DK353884D0 (da) 1984-07-19
EP0139105A1 (de) 1985-05-02
US4541410A (en) 1985-09-17
CA1245920A (en) 1988-12-06
DE3466273D1 (en) 1987-10-22
DK136791A (da) 1991-07-17
IE56071B1 (en) 1991-04-10
EP0199369A2 (de) 1986-10-29
CA1258411C (de) 1989-08-15
DK171187B1 (da) 1996-07-15
DK353884A (da) 1985-01-21
EP0199369A3 (en) 1987-01-21
IE56070B1 (en) 1991-04-10
DK162952B (da) 1991-12-30
DK136791D0 (da) 1991-07-17
EP0199369B1 (de) 1989-09-13
DE3479754D1 (en) 1989-10-19
IE841868L (en) 1985-01-20

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